Pull-off for sewing machines



Sept. 10, 1929. J, MANN 1,727,614

PULL-6FF FOR SEWING MACHINES Filed June 1, 1927 3 Sheets-Sheet 1 Sept. 10, 1929.

, J. MANN PULL-OFF FOR SEWING MACHINES Filed June 1, 1927 3 She'et s-Sheet 2 kikfvmwTar} Sept. 10, 1929. J. MANN PULL-OFF FOR SEWING MACHINES Filed June 1, 1927 3 Sheets-sheaf; 5

0 device includes means Patented Sept. 10, 1929.

entree sra'rss amen f PATENT oFF ca i JOSEPH MANN,

or PHILADELPHIA, I PENNSYLVANIA, ,AssIGNoR' To UNIoNf SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PULL-OFF Fen SEWING MACHINES.

Application filed June 1,

15 pulls not only needle thread, and looper thread from the supply, but releases the thread drawn off while the presser foot is still raised. i

A further object of the invention is to pro- 20 vide means of the above character wherein ill the releasing means for releasing the thread drawn oil is automatically operated by the raising, oi the presser foot, and wherein the time of release maybe varied for varying the amount of thread drawn off.

These and other objects will in part be obvious and will in part behereinafter more fully disclosed. l I

In the drawings which show by way of illustration one embodiment of the invens tion- Figure 1 is a front view of a portion of a sewing machine having my improvements applied thereto;

Fig. 2 is a rear view of the same;

Fig". 3 is a view partially in section and partially in broken lines from the rear, show ing the threads as drawn oil and the devices released for giving up thread;

Fig. 4 is a view in perspective showing a portion of the pull-oil device and the adjustable cam for releasing the pulheii members; and

Fig, 5% is a detail showing; in perspec ive 1927. Serial No. 195,732.

a portion of the link of the pull-0E device and the latch which cooperates therewith.

Theinventionis directed broadly to a pulled for sewing machines for pulling the needle thread and also the looper thread from the supply when the presser foot is raised. This is accomplished by a rock leveril'laving anarm which engages the needle thread so that wl'ienthe rocklever is oscillatecha needle thread will be pulled trom'the supply, the amount ofthread pulled depending the extent of movement otthe arm. A second arm is connected to the rock lever so as to move therewith, and this second arm is provided with a device for engagingthe looper thread and pulling a certain amount of loop er thread from the supply, depending upon I the 'extent of movement of therock lever. The rock lever is connected to arock frame which in turn is connected to thepresser bar. Theconnection between therock lever and the rock frame includes :a telescoping link and latch for holding nape-ts of the link in rigid fixed relation to each other. When the parts are latched together, and the presser foot is raised, the rock arm will be oscillate; and needle thread will be drawn irom the supply, and likewise looper thread drawn fromthe supply. WVhen a proper amountof thread is drawn, the latchis automatically released, and this releases the telescoping parts otthe link, and the spring returns the roek arm to its normal. position thus giving up the thread drawn ollp This occurs while the presser foot is, still raised. 1,

Referring more in detail'to the drawings, my invention isshown as applied to a sewing machine having a standard 1 carrying'an overhanging arm 2 and a cylindrical work supporting arm 3.- At theouter end of the overhanging arm 2 is a needlebar 4; carrying needles 5, 5. Cooperating with the needles in the work supporting cylinder is a thread ca1-rying1ooper. The needles are supplied with the threads a, '22., There a leeper m operating with each needle, and the loopers I aresupplied with looper threads Z, Z.

The needle bar 4 is reciprocated by a needle lever 6. Associated with the needle lever are thread gu des 7 and 8 for the needle threads. On the upper end of the needlebar is a needle thread guide 9. The material is held on the work support by a presser foot 10 carried by the presser bar 11. The presser bar is adaptedto be raised by means of a lever 12 pivoted at 13 to the overhanging arm 2. The forward end of the lever extends beneath the projecting lug ll on the presser bar.

A spring 15 presseson said lug and holdsthe presser bar in its loweredposit-ion. When the lever 12 is oscillated, the presser bar will be raised. Mounted on the lever 12 is an arm- 16 which, together with the lever 12, forms a rock frame. Mounted on the overhanging arm 2 of the machine is a rock arm 17. This rockarm 17 is mounted on a stud 18 secured to the overhanging arm 2 by a set screw 19. The rock arm 17 is,in reality, provided with two arms, one of'which is substantially, horizontal, and the other vertical. The horizontal:arm carries a plate 20 which is secured to thehorizontal arm.- by screws 21, 21. The plate 20 is providedwith a bracket 22 which extends outwardly, thence laterally at 23,

/ thence'downwardly at 24, thence laterally again and upwardly at 25, forming a hookshaped end adapted, to engage the needle threads, as, clearly shown in Fig. 3 of the drawings. This hook-shaped end of the bracket 22 engages the needle threads between the thread guide 8 on the ,needle'lever,

and the thread guide 26 carried by a lever 2'7 which has connection with the presser bar. It will readily be seen that when the rock arm is oscillated, the hook-shaped end of the bracket 22 will engage the needle threads, and as thishook-shaped end moves away from the thread guides 8 and 26, it will draw thread through the thread guide 8 and the tensions27, 27 from the supply.

The rock: arm '17 is provided with a sleeve hub. 28, and an arm29 issecured thereto.

This arm 29 oscillates with the rock arm 1'7.

' The arm 29 is connected toa rod 39. This fill rod extends down alongside the standard 1 and slides vertically in a bracket 31. The rod is provided with an arm 32 which projects laterally from the'rod, thence upwardly at 33, where itis slightly ofiset and bent downwardly at 34. This forms hook-shaped bracket arm which engages the looper threads Z,Z, between the guide tube '35 and theten sion 36 shown in broken lines in Fig, 3 of the drawings. A spring 37 is attached to the bracket 31 and to the rod 30, and normally tends to raise the rod to bring the upper hooked end slightly above the path of normal travel of the looperthreads. When the rodis depressed, said hooked end will move away from the guide and pull the looper thread from the supply. The amount of thread drawn from the supply depends upon the extent of movement of the rod 30. The spring 37 will return the rod to its normal position, and thus give up the thread drawn off when the rod is released. The same is true of the needle threads. The oscillation of the rock arm 17 which moves the rod 30 to cause the looper threads to be drawn from the supply, also draws the needle threads from the supply, and the spring which returns the rod 30, so as to give up the thread drawn offlreturns the rock arm and gives up the needle thread.

The rock arm is oscillated. by. a link con nection with the arm 16 attached. to the presser foot lifting lever. The link is a telescoping link, formed of two sections 38 and 39. The section 39 is provided with a recess 40=which forms the end or" thesection into a sleeve, and the'section 33 slides within this sleeve. The section 38 is provided with a notch ell. The sleeve part of the section 39 is provided with spaced upstanding lugs: 42, between which is pivoted a latch 43. The latch 43 has the end. ll thereof extended at right angles, and shaped to engage and fit the notcn ed. A spring 45 normally holds of the latch extends to engage the no.ch.

When thepartsoithe link are latched together, then thedownward movement on the left-hand end of the presser bar lifting lever, as viewed in Fig. 2, will move the arm 16 in a counter-clockwise direction, and this, through the link, will oscillate the rock arm 1'? in a counter clockwise direction, causing needlethread to be drawn from the supply, and also causing looper thread to be drawn from the supply. This drawing of the threads from the supply occurs, therefore, at the time when the presser toot-is raised. lt is desired to remove the fabric from the machine while the presser foot is still raised, and therefore, it is. an advantage to give up this thread drawn oil to permit the removal of the fabric and a proper amount of thread to be drawn through the eyes oi the needles and the eyes of the loopers, so that when the threads are severed, there is ample supply of thread to insnre'a stitch formation when the stitching ot the next article begins.

In ord r that the thread drawn oii' may e 'iven up while'the presser foot is raised,

latch 4-3 is provided with a projecting arm l9. When the rock arm 17 is oscillated, the releasing cam l6 moves therewith. The oscillating movement of the rock arm which draws thread from the supply, brings this releasing cam into contact with the arm 49 of the latch, and will lift the latch. ll hen the latch is lifted, then the section 38 is released from the section 39. The recess 40 is of sufficient length so as to permit the section 38 to move further into the section 39. This movement of the rock arm I? is brought about by the spring 37.

IVhen the presser bar is raised, the pull-off device will be operated to pull thread from the supply, and this pull-off device will also be automatically released from the presser bar lifting means, so that the spring may re turn the pulled devices to their normal position and thus give up the amountof thread drawn off. This, of course, takes place while the presser foot is still raised. T he time of release can be varied by adjusting the position of the releasing cam, and therefore, the amount of thread drawn oil can be varied by adjusting the releasing cam.

t is obvious that minor changes in the details of construction and the arrangement of the parts may be made without departing from. the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is

1. In a sewing machine, the combination of a needle, a presser foot, and means for raising said presser foot and pulling needle thread from the supply, said means including devices for automatically releasing the thread pulled off while thepresser foot is still raised, said automatic releasing devices being adjustable whereby the amount of thread drawn oil may be varied.

2. In a sewing machine, the combination of a needle, a thread carrying looper cooperating with said needle, a presser foot, and means for raising said presser foot and pulling needle thread and looper thread from the supply, said means including devices for automatically releasing the thread pulled 01f while the presser foot is still raised, said automatic releasing devices being adjustable whereby the amount of needle thread and looper thread drawn oil may be varied.

3. In a sewing machine, the combination of a needle, a presser foot, a lever for lifting said presser foot, a rock frame oscillated thereby, a rock arm, means actuated by said rock arm for pulling needle thread from the supply and pulling looper thread from the supply, devices for connecting said rock frame and said rock arm, said devices including a releasable means whereby said rock arm may be released from its connection to the rock frame and the amount of thread drawn ofi given up while the presser foot is still raised, and an adj ustablereleasmg cam for releasing the connectionbetween the rock frame and the rock arm.

4, In a sewing machine, the combination of a needle,a presser foot, a lever for lifting said presser feet, a rock frame oscillated thereby, a rock arm, means actuated by said rock arm for pulling needle thread from the supply and pulling looper devices for connectingsaidrock frame and said rock arm, said devices including a releasable means whereby said rock arm may be released from its connection to the rock frame and the amount of thread drawn off given up while the presser foot is still raised, an adjustable releasing cam for releasing the connection between the rock frame and the rock arm, and a spring for returning the rock arm to normal position when released.

5. In a sewing machine, the combination of a needle, a thread carrying looper, a presser foot, a presser foot lifting lever, an arm car ried thereby forming a rock frame, a rock arm,

a bracket connected to said rock arm and adapted to engage the needle-thread for drawing thread from the supply when said rock arm is oscillated, a rod connected to the rock arm, a bracket carried by the rod and adapted to engage the looper thread for drawing thread from the supply when the rock arm is oscillated, releasable devices for connecting the rock frame and the rock arm, said releasable devices including a link having telescoping parts, a latch carried by one part and adapted to engage the other for holding the parts in rigid connection, whereby when the presser foot is raised, the rock arm will be movedfor drawing threads from the supply, an adjustable cam carried by the rock arm adapted to engage the latch and release the latch when the proper amount of thread is drawn from the supply, and a spring for returning the rock arm to normal position when released from the rock frame, thus giving up the thread drawn from the supply while the presser foot is still raised.

6. In a sewing machine, the combination of a needle, a presser foot, a lever for lifting the presser foot, a rock frame oscillated thereby, a rock arm for pulling needle thread from the supply, a sectional link for connecting said rock arm to said rock frame, latching means for connecting the sections of said link, and,

means for releasing the latch while the presser foot is still raised.

- 7. In a sewing machine, the combination of a needle, a presser foot, a lever for lifting the presser foot, a rock frame oscillated thereby, a rock arm for pulling needle thread from the supply, a sectional link for connecting said rock arm to said rock frame, latching means for connecting the sections of said link, and adjustable means for releasing the latch while the presser foot is still raised.

8. In a sewing machine, the combination of thread from the supply,

a needle, a presser foot, a lever for lifting the resser foot, a rock frame oscillated thereby, arock arm for pulling needle thread from the supply, a sectional link for connecting said rock arm to saidrock frame, latching means for connecting the sections of said link and means for releasing the latch While the presser foot is still raised, said latch operating automatically to connect said sections When the presser foot is lowered.

In testimony whereof, I aflix my signature.

JOSEPH MANN. 

